Safety for mitral valve implant

ABSTRACT

A heart valve implant may include a shaft extending generally along a longitudinal axis of the heart valve implant. A spacer may be coupled to the shaft between a first and a second end region of the shaft. The spacer may be configured to interact with at least a portion of at least one cusp of a heart valve to at least partially restrict a flow of blood through the heart valve in a closed position and at least one anchor may be configured to be coupled to the first end region of the shaft. At least one safety stop may extend generally radially outwardly from the longitudinal axis of the heart valve implant beyond at least a portion of an outer perimeter of the spacer. The safety stop may include a cross-section which is greater than a cross-section of the heart valve in at least one dimension. The safety stop may also be configured to at least partially restrict a movement of the heart valve implant with respect to the heart valve in at least one direction.

CROSS-REFERENCE TO RELATED APPLICATION

The subject application is a continuation-in-part of co-pending U.S.patent application Ser. No. 11/258,828, entitled “Heart Valve Implant”filed on Oct. 26, 2005, which is hereby incorporated by reference.

FIELD

The present disclosure relates to the repair and/or correction ofdysfunctional heart valves, and more particularly pertains to heartvalve implants and systems and methods for delivery and implementationof the same.

BACKGROUND

A human heart has four chambers, the left and right atrium and the leftand right ventricles. The chambers of the heart alternately expand andcontract to pump blood through the vessels of the body. The cycle of theheart includes the simultaneous contraction of the left and right atria,passing blood from the atria to the left and right ventricles. The leftand right ventricles then simultaneously contract forcing blood from theheart and through the vessels of the body. In addition to the fourchambers, the heart also includes a check valve at the upstream end ofeach chamber to ensure that blood flows in the correct direction throughthe body as the heart chambers expand and contract. These valves maybecome damaged, or otherwise fail to function properly, resulting intheir inability to properly close when the downstream chamber contracts.Failure of the valves to properly close may allow blood to flow backwardthrough the valve resulting in decreased blood flow and lower bloodpressure.

Mitral regurgitation is a common variety of heart valve dysfunction orinsufficiency. Mitral regurgitation occurs when the mitral valveseparating the left coronary atrium and the left ventricle fails toproperly close. As a result, upon contraction of the left ventricleblood may leak or flow from the left ventricle back into the leftatrium, rather than being forced through the aorta. Any disorder thatweakens or damages the mitral valve can prevent it from closingproperly, thereby causing leakage or regurgitation. Mitral regurgitationis considered to be chronic when the condition persists rather thanoccurring for only a short period of time.

Regardless of the cause, mitral regurgitation may result in a decreasein blood flow through the body (cardiac output). Correction of mitralregurgitation typically requires surgical intervention. Surgical valverepair or replacement is carried out as an open heart procedure. Therepair or replacement surgery may last in the range of about three tofive hours, and is carried out with the patient under generalanesthesia. The nature of the surgical procedure requires the patient tobe placed on a heart-lung machine. Because of theseverity/complexity/danger associated with open heart surgicalprocedures, corrective surgery for mitral regurgitation is typically notrecommended until the patient's ejection fraction drops below 60% and/orthe left ventricle is larger than 45 mm at rest.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantage of the claimed subject matter will be apparentfrom the following description of embodiments consistent therewith,which description should be considered in conjunction with theaccompanying drawings, wherein:

FIG. 1 is a perspective view of an embodiment of a mitral valve implantconsistent with the present disclosure;

FIG. 2 a depicts an embodiment mitral valve implant consistent with thepresent disclosure implanted within a heart in an open position;

FIG. 2 b depicts an embodiment mitral valve implant consistent with thepresent disclosure implanted within a heart in a closed position;

FIG. 3 is a perspective view of another embodiment of a mitral valveimplant consistent with the present disclosure;

FIG. 4 depicts the mitral valve implant consistent with FIG. 3 implantedwithin a heart in an open position according to the present disclosure;

FIG. 5 depicts a further embodiment of a mitral valve implant consistentwith the present disclosure;

FIG. 6 depicts yet another embodiment of a mitral valve implantconsistent with the present disclosure;

FIGS. 7-9 depict additionally embodiments of a mitral valve implantconsistent with the present disclosure; and

FIG. 10 depicts a mitral valve implant without a spacer consistent withthe present disclosure.

DESCRIPTION

Referring to FIG. 1, a perspective view of one embodiment of a mitralvalve implant 10 is depicted. As shown, mitral valve implant 10 maygenerally include a spacer or valve body portion 12 which may be coupledto a shaft 14. The shaft 14 may be coupled to at least one anchorportion 16 configured to couple, attach, and/or otherwise secure themitral valve implant 10 to native coronary tissue. In general, at leasta portion of the spacer 12 may be configured to be disposed proximate amitral valve such that the mitral valve implant 10 may interact and/orcooperate with at least a portion of the native mitral valve 18 toreduce and/or eliminate excessive regurgitation as illustrated in FIG.2.

The mitral valve implant 10, FIG. 1, may also include one or more safetystops 20. The safety stops 20 may at least partially reduce, restrictand/or prevent the mitral valve implant 10 from moving away from themitral valve 18 area in at least one direction should the anchor portion16 become dislodged or allows excessive movement of the mitral valveimplant 10. The safety stops 20 may be configured to extend generallyradially outwardly from the longitudinal axis L of mitral valve implant10 beyond at least a portion of an outer perimeter of the spacer 12 suchthat the safety stops 20 may at least partially reduce, restrict and/orprevent the mitral valve implant 10 from moving away from the mitralvalve 18 area in at least one direction. According to one aspect, thesafety stops 20 may define an outer perimeter and/or cross-section thatis larger in at least one direction than the mitral valve 18. Forexample, the safety stops 20 may define an outer perimeter and/orcross-section that is larger in at least one direction than theperimeter and/or cross-section of the spacer 14.

For example, the safety stops 20 may be configured to reduce and/orprevent the mitral valve implant 10 from moving through the mitral valve18 in at least one direction. According to this embodiment, the safetystop 20 may allow a portion of the mitral valve implant 10 to move withrespect to the mitral valve 18; however, the safety stop 20 may prevent,restrict and/or reduce the ability of the entire mitral valve implant 10from passing through the mitral valve 18. It should be noted that thesafety stops 20 need only prevent, restrict and/or reduce the mitralvalve implant 10 from passing through the mitral valve 18. The safetystop 20 does not necessarily have to restrict the movement of the mitralvalve implant 10 sufficiently to allow the mitral valve implant may tocontinue to interact and/or cooperate with the mitral valve leaflets 19and reduce and/or eliminate excessive regurgitation. In other words, thesafety stop 20 may allow the mitral valve implant 10 to move such thatthe mitral valve implant 10 no longer interacts and/or cooperates withthe mitral valve leaflets 19 and no longer reduces and/or eliminatesexcessive regurgitation. The safety stop 20 according to this aspectneed only prevent, restrict and/or reduce the mitral valve implant 10from passing through the mitral valve 18.

Additionally (or alternatively), the safety stops 20 may be configuredto sufficiently reduce, restrict and/or prevent the movement of themitral valve implant 10 (and in particular, the spacer 12) such that thespacer 12 may continue to interact and/or cooperate with at least aportion of the mitral valve 18 to reduce and/or eliminate excessiveregurgitation. It should be noted that the safety stops 20 do notnecessarily have to be configured to prevent the mitral valve implant 10from moving at all or from moving away from an original, preferred, oroptimized position with respect to the mitral valve 18. As such, thesafety stops 20 may allow the mitral valve implant 10 to move withrespect to the mitral valve 18 as long as a minimum degree ofinteraction and/or cooperation exists between the mitral valve implant10 and at least a portion of the mitral valve leaflets 19. The minimumdegree of interaction and/or cooperation between the mitral valveimplant 10 and at least a portion of the mitral valve leaflets 19 mayvary and may be determined experimentally.

As shown in FIG. 1, the mitral valve implant 10 may include at least onesafety stop 20 disposed generally above the spacer 12. For example, themitral valve implant 10 may include a safety stop 20 a extendinggenerally radially outwardly from the longitudinal axis L of mitralvalve implant 10 along at least a portion of the shaft 14. As usedherein, the term “above” the spacer 12 refers to a portion of the mitralvalve implant 10 between spacer 12 and a first end 23 of the mitralvalve implant 10 which is intended to be disposed proximate the atrium(e.g., the left atrium 22). The safety stop 20 a may be disposedproximate the distal portion of the first end 23 of the shaft 14 asshown, however, the safety stop 20 a may be disposed anywhere along theportion of the mitral valve implant 10 between spacer 12 and the distalportion of the first end 23 of the shaft 14. For example, the safetystop 20 a may be disposed proximate the spacer 12. As shown in FIG. 2,the safety stop 20 a may be configured to be disposed generally withinthe left ventricle 24.

Referring to FIG. 3, the mitral valve implant 10 may include at leastone safety stop 20 disposed generally below the spacer 12. As usedherein, the term “below” the spacer 12 refers to a portion of the mitralvalve implant 10 between spacer 12 and a second end 24 of the mitralvalve implant 10 which is intended to be disposed proximate theventricle (e.g., the left ventricle 24). For example, the mitral valveimplant 10 may include a safety stop 20 b extending generally radiallyoutwardly from the longitudinal axis L of mitral valve implant 10 alongat least a portion of the shaft 14. As shown in FIG. 4, the safety stop20 b may be configured to be disposed generally within the left atrium22. While the mitral valve implant 10 is shown having safety stops 20 a,20 b disposed above and below the spacer 12, the mitral valve implant 10may include only the safety stop 20 b.

Alternatively (or in addition), the mitral valve implant 10 may includea safety stop 20 c, FIG. 5, extending generally radially outwardly fromthe longitudinal axis L of mitral valve implant 10 about the anchorportion 16. The safety stop 20 c may be disposed proximate the shaft 14,however, one or more safety stops 20 c may be disposed along otherpositions of the anchor portion 16. Again, while the mitral valveimplant 10 is shown having safety stops 20 a, 20 b disposed above andbelow the spacer 12, the mitral valve implant 10 may include only thesafety stop 20 c.

Referring to FIG. 6, the mitral valve implant 10 may include at leastone safety stop 20 d extending generally radially outwardly from thelongitudinal axis L of mitral valve implant 10 along the spacer 12.According to one embodiment, the safety stop 20 d may be disposedproximate either the first or the second ends 23, 24 of the mitral valveimplant 10. Placing the safety stop 20 d proximate either the first orsecond ends 23, 24 of the mitral valve implant 10 may increase thesurface available to the spacer 12 to interact and/or cooperate with themitral valve leaflets 19 to reduce and/or eliminate excessiveregurgitation and may reduce the likelihood of the safety stop 20 d frompreventing the spacer 12 from interacting and/or cooperating with themitral valve leaflets 19 to reduce and/or eliminate excessiveregurgitation.

Those skilled in the art will recognize that while the mitral valveimplant 10 in FIGS. 2-6 are shown in combination with the safety stop 20a disposed above the spacer 12, the mitral valve implant 10 does notnecessarily have to include the safety stop 20 a. The mitral valveimplant 10 may include one or more or a combination of two or more ofthe safety stops 20 a-20 d.

As discussed above, the safety stops 20 may reduce and/or prevent themitral valve implant 10 from moving away from the mitral valve 18 areashould the anchor portion 16 become dislodged or allows excessivemovement of the mitral valve implant 10. For example, the safety stops20 may define an outer perimeter and/or cross-section that is larger inat least one direction than the mitral valve 18. As such, the safetystop 20 may include a variety a configurations and/or geometriesdepending on the intended application. The safety stop 20 may be shapedto facilitate the flow of blood from the left atrium 22 to the leftventricle 24 when the mitral valve 18 is open. The safety stop 20 mayhave a generally streamlined shape, allowing the smooth flow of bloodaround the safety stop 20. Other embodiments of the mitral valve implant10 may provide less consideration for the flow characteristics of bloodflowing around the safety stop 20.

According to one aspect, the safety stop 20 may have a generallyannular, ring-like shape and may define an outer perimeter extendingapproximately 360 degrees around the radius of the mitral valve implant10. For example, the safety stop 20 may include a generally circular,oval, or elliptical outer perimeter as generally shown in FIGS. 1-6. Inany event, the outer perimeter of the safety stop 20 may be configuredto restrict the movement of the mitral valve implant 10 through themitral valve 18. The safety stop 20 may be configured to be mounted,attached, coupled, or otherwise secured to the mitral valve implant 10using one or more spokes, ribs, stringers, or supports 26. As such, thesafety stop 20 may form a generally open, frame-like structure.Alternatively (or in addition), the safety stop 20 may be configured asa substantially solid geometry or shape. According to one embodiment,the safety stop 20 may include a generally solid, disc-like structure.The substantially solid geometry safety stop 20 may optionally includeone or more apertures or openings that allow fluid to pass through thesafety stop 20.

The safety stop 20 may also include one or more segments or components30 extending generally radially outwardly from the mitral valve implant10 as shown in FIGS. 7-9. Each segment 30 may extend generally outwardlyless than 360 degrees along the radius of the mitral valve implant 10.For example, the safety stop 20 may include a single segment 30 a asshown in FIG. 7. The single segment 30 a may extend generally radiallyoutwardly less than 360 degrees along the radius of the mitral valveimplant 10. The single segment 30 a may extend outwardly from mitralvalve implant 10 in at least one direction such that an outer perimeterand/or cross-section of the mitral valve implant 10 is larger in atleast one direction than the cross-section of the mitral valve 18.Alternatively, the safety stop 20 may include a plurality of segments 30a-30 n as shown in FIGS. 8 and 9. The plurality of segments 30 a-30 nmay be spaced evenly and/or unevenly about the radial direction of themitral valve implant 10. While each segment 30 a-30 n may extend lessthan 360 degrees along the radius of the mitral valve implant 10, thesum of the segments 30 a-30 n may be equal, less than, or greater than360 degrees. Again, the plurality of segments 30 a-30 n may extendoutwardly from mitral valve implant 10 in at least one direction suchthat an outer perimeter and/or cross-section of the mitral valve implant10 is larger in at least one direction than the cross-section of themitral valve 18.

According to one embodiment, the segments 30 may have a generallytear-drop like shape. However, the segments 30 may include other shapessuch as, but not limited to, circles, ovals, rectangles, triangles, andthe like. The segments 30 may form a generally wire-like frame as shownin FIGS. 7 and 8. The wire-like frame may facilitate the flow of fluidpast the safety stop 20.

The segments 30 may also have a generally solid geometry or shape asshown in FIG. 9. The solid segments 30 may optionally include one ormore openings, apertures, or passageways 32 configured to allow fluid topass through the solid segment 30. As used herein, the phrases“generally solid geometry”, “substantially solid geometry”, or the likeare intended to mean a geometry having an outer surface that defines asubstantially fixed or constant volume. That is, a volume of thesegments 30 does not substantially change before and after implantationof the mitral valve implant 10. A “generally solid geometry” mayinclude, without limitation, a solid, semi-solid, or porous (e.g.,micro- or nano-scale pores) material.

At least a portion of the safety stop 20 may be collapsible and/orreducible in volume to facilitate percutaneous and/or transluminaldelivery of the mitral valve implant 10. In such a manner, the safetystop 20 of the mitral valve implant 10 may be a collapsible member,which can be reduced in volume and/or reduced in maximum diameter duringdelivery to the heart and/or during placement and/or attachment of theanchor to native coronary tissue. After delivery to the heart, thesafety stop 20 may be expanded, inflated, and/or otherwise increased involume or size. Accordingly, the mitral valve implant 10 may bedelivered to an implantation site via a smaller diameter catheter,and/or via smaller vessels, than would otherwise be required.

The at least partially deformable safety stop 20 may be collapsed to areduced size, which may, for example, allow the mitral valve implant 10to be loaded into a catheter delivery system. Such a catheter deliverysystem may be suitable for transluminal delivery of a mitral valveimplant 10, including the safety stop 20, to the heart. In addition tobeing collapsed, the safety stop 20 may be deformed to facilitateloading into a catheter delivery system. For example, the safety stop 20may be collapsed and may be rolled and/or folded to a generallycylindrical shape, allowing the safety stop 20 to be loaded in acatheter having a circular lumen.

A collapsed and/or rolled or folded safety stop 20 may be inflated,restoring the safety stop 20 to expanded configuration. For example, acollapsed and/or rolled or folded safety stop 20 may be inflated andrestored to an expanded configuration once the mitral valve implant 10has been delivered to the heart and deployed from a catheter deliverysystem. Inflating the safety stop 20 may be carried out by introducing afluid, such as saline, into the at least one cavity of the safety stop20. In addition to a liquid, such as saline, the safety stop 20 may beinflated with a setting or curable fluid. The setting or curable fluidmay set and/or be cured to a solid and/or semi-solid state within thecavity of the safety stop 20. An example of such a material may be athermoset polymer resin, a gel material, such as silicone gel, etc.

At least a portion of the safety stop 20 may also be constructed from ashape-memory material. For example, at least a portion of the safetystop 20 may include a shape-memory alloy such as, but not limited to,copper-zinc-aluminum, copper-aluminum-nickel, and nickel-titanium (NiTi)alloys. The shape-memory alloy may include either one-way or two-wayshape memory and may be introduced in to the delivery catheter lumenhaving a shape which does not exceed the interior dimensions of thedelivery catheter lumen. For example, the safety stop 20 may have agenerally elongated or generally helical shape. Upon delivery toproximate the mitral valve, the shape-memory safety stop 20 may beheated to cause the safety stop 20 to deform into the desired shape forinstallation.

According to another embodiment, the safety stop 20 may be formed fromone or more separate segments 30 which are each no larger than theinterior, radial dimensions of the delivery catheter lumen in at leastone direction. The segments 30 do not need to be expanded/inflated, butrather may be configured to be mounted, coupled, attached, or otherwisesecured to the mitral valve implant 10 once delivered proximate themitral valve. The size and shape of the segments 30 may be varied bydesign and quantity such that the constructed safety stop 20accommodates the patient's anatomy, etiology of valve regurgitation, aswell as the physical limitations of the implant delivery system.

At least a portion of the safety stop 20 may also be coated orencapsulated with various compliant materials such as, but not limitedto, porous synthetic materials (for example, polyesters) that promotecell growth to improve biocompatibility and improve attachment betweenthe safety stop 20 and the native coronary tissue. Other coatingmaterials include non-reactive synthetics (for example,silicone/urethane composites) and xenograft (animal pericardium orcollagen) materials.

While the safety stop 20 has been shown extending generally 90 degreesradially outwardly from the mitral valve implant 10, one or more of thesafety stops 20 may extend generally radially outwardly at one or moreangles greater than or less than 90 degrees from the longitudinal axis Lof the mitral valve implant 10. Additionally, the safety stops 20 may belocated at a fixed position along the mitral valve implant 10 or may bemovable along the longitudinal axis L of the mitral valve implant 10.Accordingly, the safety stop 20 may be positioned along the longitudinalaxis L of the mitral valve implant 10 to minimize possible movement ofthe mitral valve insert 10 and/or to position the safety stop 20 tominimize potential interference with the surrounding tissue. Forexample, the safety stop 20 may include a ratchet-like mechanism. Thesafety stops 20 may also be located about a common, radial plane of themitral valve implant 10 and/or may be located about two or more radialplanes of the mitral valve implant 10.

It should be noted that while the mitral valve implant 10 has beendescribed in combination with a spacer 12, the mitral valve implant 10may optionally include only the shaft 14, the anchor portion 16, and oneor more safety stops 20 as generally shown in FIG. 10. Additionally, atleast a portion of the shaft 14 may include a substantially rigid shaftwhich is configured to be substantially self-supporting. Alternatively(or in addition), at least a portion of the shaft 14 may include awire-like shaft. According to this aspect, the first and second ends 23,24 of the shaft 14 may each include anchor portions 16.

The spacer 12 of the mitral valve implant 10 shown in FIGS. 1-9 may haveany shape known to those skilled in the art. For example, as shown inFIG. 1, the spacer 12 may have a generally tapered shape, including asidewall 17 tapering outwardly from a narrow portion 40 adjacent to oneor more of the ends of the spacer 12 to an enlarged portion 42. Thetaper of the sidewall 17 may have a flared or belled shape, providing anat least partially concave geometry. In various other embodiments, thespacer 12 may include a sidewall 17 having a generally uniform taper,providing a straight profile. In still other embodiments, the sidewall17 of the spacer 12 may exhibit a convex taper, producing an at leastsomewhat bulging tapered profile.

The enlarged portion 42 of the spacer 12 may have an arcuate profilearound the circumference of the proximal region of the enlarged portion42. The bottom 44 of the enlarged portion 42 may be provided having aflat and/or arcuate shape. Furthermore, the bottom 44 of the proximalregion may include convex and/or concave contours.

According to an embodiment, the spacer 12 may be slidably coupled to theshaft 14. The spacer 12 may include an opening 46 extending from thebottom 44 of the enlarged portion 42, through the spacer 12, and to thenarrow portion 40. In one such embodiment, the opening 46 may extendgenerally axially through the spacer 12. The opening 46 may be sized toslidably receive at least a portion of the shaft 14 therethrough. Theshaft 14 may include one or more stops 48, 50. The stops 48, 50 may besized and/or shaped to control and/or restrict translation of the spacer12 along the shaft 14 beyond the respective stops 48, 50. In thismanner, in the illustrated embodiment, translation of the spacer 12along the shaft 14 may be restricted to the expanse of the shaft 14between the stops 48, 50.

One or more of the stops 48, 50 may be integrally formed with the shaft14. Furthermore, one or more of the stops 48, 50 may be provided as aseparate member coupled to and/or formed on the shaft 14. In anembodiment in which one or more of the stops 48, 50 are integrallyformed with the shaft 14, the spacer 12 may be slidably coupled to theshaft 14 by pressing the spacer 12 over at least one of the stops 48,50, which may at least partially elastically deform the opening 46 topermit passage of at least one of the stops 48, 50. Once the one or moreof the stops 48, 50 have been pressed through the opening 46, theopening 46 may at least partially elastically recover, thereby resistingpassage of the one or more stops 48, 50 back through the opening 46.Various other arrangements may be employed for providing stops on theshaft and/or for controlling and/or limiting translation of the spaceralong the shaft.

The anchor portion 16 may include a helical member 52 coupled to theshaft 14. As shown, the helical member 52 may be loosely wound such thatadjacent turns of the helical member 52 do not contact one another, forexample resembling a corkscrew-type configuration. The anchor portion 16may be engaged with tissue by rotating the anchor portion 16 about theaxis of the helical member 52, thereby advancing the anchor portion 16into tissue. Consistent with such an embodiment, the anchor portion 16may resist pulling out from the tissue. The anchor portion 16 may beprovided as an extension of the shaft 14 wound in a helicalconfiguration. Consistent with related embodiments, the anchor portion16 may be formed as a separate feature and may be coupled to the shaft14, e.g., using mechanical fasteners, welding, adhesive, etc.

According to various alternative embodiments, the anchor portion 16 mayinclude various configurations capable of being coupled to and/orotherwise attached to native coronary tissue. For example, the anchorportion 16 may include one or more prongs adapted to pierce coronarytissue and to alone, or in conjunction with other features, resistremoval of the anchor portion 16 from tissue. For example, the anchorportion 16 may include a plurality of prongs which may engage nativecoronary tissue. According to various other embodiments, the anchorportion 16 may include features that may facilitate attachment bysuturing. Exemplary features to facilitate suturing may include rings oropenings, suture penetrable tabs, etc. Various other anchor portions 16that may allow attachment or coupling to native coronary tissue may alsosuitably be employed in connection with the present disclosure.

Turning to FIGS. 2 and 4, the mitral valve implant 10 is shown implantedwithin a heart 102. The mitral valve implant 10 may be disposed at leastpartially within the left ventricle 24 of the heart 102. As shown, theanchor portion 16 may be engaged with native coronary tissue withinand/or adjacent to the left ventricle 24. The shaft 14, coupled to theanchor portion 16, may extend into the left ventricle 24. The shaft 14may further extend at least partially within the mitral valve 18, i.e.,the shaft 14 may extend at least partially between the cusps or leaflets19 of the mitral valve 18, and may also extend at least partially intothe left atrium 22. The spacer 12 of the mitral valve implant 10 may bepositioned at least partially within the left ventricle 24 with theenlarged portion 42 within the left ventricle 24 and with the narrowportion 48 positioned at least partially within and/or pointed towardsthe left atrium 22.

FIGS. 2 a and 4 depict the heart 102 in a condition in which thepressure of blood within the left atrium 22 is at equal to, or higherthan, the pressure of blood within the left ventricle 24, e.g., duringcontraction of the left atrium 22. As shown, when the pressure of bloodwithin the left atrium 22 is greater than or equal to the pressure ofblood within the left ventricle 24, blood may flow from the left atrium22 into the left ventricle 24. The pressure differential and/or the flowof blood from the left atrium 22 to the left ventricle 24 may slidablytranslate the spacer 12 along the shaft 14 toward the left ventricle 24,in the direction of blood flow between the chambers.

Sliding translation of the spacer 12 along the shaft 14 may at leastpartially withdraw the spacer 12 from the mitral valve 18 to an openposition, as shown. When the spacer 12 is at least partially withdrawnfrom the mitral valve 18, a passage may be opened between the spacer 12and the mitral valve 18, allowing blood to flow from the left atrium 22to the left ventricle 24. Translation of the spacer 12 away from themitral valve 18 may be controlled and/or limited by the stop 50. In theopen position, the stop 50 may maintain the spacer 12 in generalproximity to the mitral valve 18 while still permitting sufficientclearance between the mitral valve 18 and the spacer 12 to permitadequate blood flow from the left atrium 22 to the left ventricle 24.Additionally, the flow of blood from left atrium 22 to the leftventricle 24 may cause the mitral valve 18 to flare and/or expandoutwardly away from the mitral valve implant 10, permitting blood flowbetween the implant 10 and the cusps 19 of the mitral valve 19.

As the left ventricle 24 contracts, the pressure of blood in the leftventricle 24 may increase such that the blood pressure in the leftventricle 24 is greater than the blood pressure in the left atrium 22.Additionally, as the pressure of the blood in the left ventricle 24initially increases above the pressure of the blood in the left atrium22, blood may begin to flow towards and/or back into the left atrium 22.The pressure differential and/or initial flow of blood from the leftventricle 24 into the left atrium 22 may act against the spacer 12 andmay translate the spacer 12 toward the left atrium 104. For example,pressurized blood within the left ventricle 24 may act against thebottom 24 of the spacer 12 inducing sliding translation of the spacer 12along the shaft 14 toward the left atrium 22.

In the closed position as shown in FIG. 2 b, the spacer 12 may betranslated toward and/or at least partially into the left atrium 22. Atleast a portion of the spacer 12 may interact with, engage, and/or bepositioned adjacent to at least a portion of the mitral valve 18. Forexample, at least a portion of at least one cusp 19 of the mitral valve18 may contact at least a portion of the spacer 12. Engagement betweenthe spacer 12 and the mitral valve 18 may restrict and/or prevent theflow of blood from the left ventricle 24 back into the left atrium 22.

In addition to the translation of the spacer 12, the mitral valve 18 mayalso at least partially close around the spacer 12, thereby alsorestricting and/or preventing the flow of blood from the left ventricle24 to the left atrium 22. For example, as mentioned above, at least aportion of one or both of the cusps 19 of the mitral valve 18 maycontact at least a portion of the spacer 12. In some embodiments, as thepressure of the blood in the left ventricle 24 increases, the pressureagainst the bottom 44 of the spacer 12 may increase. The increase inpressure against the bottom 44 of the spacer 12 may, in turn, increasethe engagement between the spacer 12 and the mitral valve 18.

Sliding translation of the spacer 12 toward the left atrium 22 may atleast partially be controlled and/or limited by the stop 48 coupled tothe shaft 14. Additionally, translation of the spacer 12 toward the leftatrium 22 may be at least partially limited and/or controlled byengagement between the spacer 12 and the mitral valve 18. One or both ofthese restrictions on the translation of the spacer 12 may, in someembodiments, prevent the spacer 12 from passing fully into the leftatrium 22. Furthermore, the diameter of the enlarged portion 20 of thespacer 12 may limit and/or restrict the movement of the spacer 12 intothe left atrium 22.

The preceding embodiment may, therefore, provide a mitral valve implantthat is slidably translatable relative to the mitral valve to reduceand/or eliminate regurgitation. Additional embodiments of a mitral valveimplant are described in co-pending U.S. patent application Ser. No.11/258,828, entitled “Heart Valve Implant” filed on Oct. 26, 2005, whichis fully incorporated herein by reference. For example, the mitral valveimplant may include a generally stationary spacer and may include morethan one anchoring portions.

The implant herein has been disclosed above in the context of a mitralvalve implant. An implant consistent with the present disclosure mayalso suitably be employed in other applications, e.g., as an implantassociated with one of the other valves of the heart, etc. The presentinvention should not, therefore, be construed as being limited to usefor reducing and/or preventing regurgitation of the mitral valve.

According to one aspect, the present disclosure features a heart valveimplant comprising a shaft extending generally along a longitudinal axisof the heart valve implant and a spacer coupled to the shaft between afirst and a second end region of the shaft. The spacer may be configuredto interact with at least a portion of at least one cusp of a heartvalve to at least partially restrict a flow of blood through the heartvalve in a closed position. At least one anchor may be configured to becoupled to the first end region of the shaft and at least one safetystop may extend generally radially outwardly from the longitudinal axisof the heart valve implant beyond at least a portion of an outerperimeter of the spacer. The safety stop may be configured to at leastpartially restrict a movement of the heart valve implant with respect tothe heart valve in at least one direction.

According to another aspect, the present disclosure features a method ofrestricting movement of a heart valve implant with respect to a heartvalve. The method may comprise providing a heart valve implantcomprising a shaft, a spacer coupled to the shaft between a first and asecond end region of the shaft, at least one anchor configured to becoupled to the first end region of the shaft, and at least one safetystop extending generally radially outwardly from the heart valve implantbeyond at least a portion of an outer perimeter of the spacer. The heartvalve implant may be at least partially collapsed and may bepercutaneously inserted into a heart where it may be secured. At least aportion of the collapsed heart valve implant may be expanded and thesafety stop may be configured to at least partially restrict a movementof the heart valve implant with respect to the heart valve in at leastone direction.

According to yet another aspect, the present disclosure features amethod of restricting the movement of a heart valve implant. The methodmay comprise engaging an anchor into coronary tissue, providing a shaftcoupled to the anchor and a spacer coupled to the shaft. The spacer maybe configured to interact with at least a portion of at least one cuspof a heart valve to at least partially restrict a flow of blood throughthe heart valve in a closed position. At least one safety stop may beprovided that extends generally radially outwardly from the heart valveimplant beyond at least a portion of an outer perimeter of the spacer.The safety stop may be configured to at least partially restrict amovement of the heart valve implant with respect to the heart valve inat least one direction.

While the depicted embodiments including expandable and/or recoverablydeformable as well as solid safety stops have generally been shownconfigured as a safety stop consistent with a translating spacer, anexpandable and/or recoverably or solid safety stop may be configured foruse as part of a valve implant including a stationary spacer. Similarly,while the valve implant embodiments including an expandable spacerand/or safety stops have been discussed in connection with transluminaland/or percutaneous delivery systems and/or procedures, such embodimentsmay also suitably be employed in connection with surgical deliverysystems and/or methods. Additionally, other features and aspects of thevarious embodiments may also suitably be combined and/or modifiedconsistent with the present disclosure. The present disclosure hereinshould not, therefore, be limited to any particular disclosedembodiment, and should be given full scope of the appended claims.

What is claimed is:
 1. A heart valve implant comprising: a shaftextending generally along a longitudinal axis of said heart valveimplant; a spacer coupled to said shaft between a first and a second endregion of said shaft, said spacer configured to interact with at least aportion of at least one cusp of a heart valve to at least partiallyrestrict a flow of blood through said heart valve in a closed position;at least one anchor configured to be coupled to said first end region ofsaid shaft; and at least one safety stop disposed between said spacerand said at least one anchor and extending generally radially outwardlyfrom said longitudinal axis of said heart valve implant, said at leastone safety stop having an outer perimeter that is larger in at least onedirection than a largest outer perimeter of said spacer when said atleast one safety stop and said spacer are both deployed in a heart, saidat least one safety stop configured to restrict a movement of said heartvalve implant through said heart valve in at least one direction, andsaid at least one safety stop has a cross-section that is greater than across-section of said heart valve in at least one dimension when said atleast one safety stop and said spacer are both deployed within saidheart.
 2. A heart valve implant according to claim 1, further comprisinga second safety stop extending generally radially outwardly from saidshaft between said spacer and said second end region of said shaft.
 3. Aheart valve implant according to claim 2, wherein said second safetystop is disposed proximate a distal most portion of said second endregion of said shaft.
 4. A heart valve implant according to claim 1,further comprising an additional safety stop extending generallyradially outwardly from said shaft between said spacer and said firstend region of said shaft.
 5. A heart valve implant according to claim 1,wherein said at least one safety stop extends generally radiallyoutwardly from said at least one anchor.
 6. A heart valve implantaccording to claim 1, further comprising a second safety stop extendinggenerally radially outwardly from said shaft between said spacer andsaid second end region of said shaft and wherein said at least onesafety stop extends generally radially outwardly from said at least oneanchor.
 7. A heart valve implant according to claim 1, wherein saidouter perimeter is generally circular.
 8. A heart valve implantaccording to claim 7, wherein said at least one safety stop includes atleast one spoke extending generally radially outwardly from said heartvalve implant to said generally circular outer perimeter.
 9. A heartvalve implant according to claim 1, wherein at least a portion of saidat least one safety stop includes a coating material configured topromote cell growth between said at least one safety stop and at least aportion of tissue adjacent said heart valve implant.
 10. A heart valveimplant comprising: a shaft; a spacer coupled to said shaft between afirst and a second end region of said shaft, said spacer configured tointeract with at least a portion of at least one cusp of a heart valveto at least partially restrict a flow of blood through said heart valvein a closed position; at least one anchor configured to be coupled tosaid first end region of said shaft; and at least one safety stopdisposed between said spacer and said at least one anchor and extendinggenerally radially outwardly from a longitudinal axis of said heartvalve implant, said at least one safety stop configured to restrict amovement of said heart valve implant through said heart valve in atleast one direction wherein said at least one safety stop is configuredto have a cross-section greater than a largest cross-section of saidheart valve in at least one dimension when said at least one safety stopand said spacer are both deployed within a heart.
 11. A heart valveimplant according to claim 10 wherein said at least one safety stop isconfigured to at least partially restrict a movement of said heart valveimplant with respect to said heart valve in at least one direction.